How do HQI spots work?
An HQI spot, also called metal halide lamp or gas discharge lamp, is a tube filled with a mixture of noble gases such as argon, xenon and krypton. Almost always other materials are present in the tube, such as the metal mercury or sodium and for some high-pressure lamps large metal halides. An electric current is running through the gas. The free electrons and ions present in the lamp conduct the current and a gas discharge is taking place. Free electrons, which are accelerated under the influence of the existing electric field, collide with the atoms of the gas and with the metal atoms. In this collision, the electrons, which are in the highest energy level of the atom, are struck to an even higher energy level. When the original energy level is relapsed, a photon or electromagnetic radiation is emitted, sometimes in the form of visible light, but also often in the form of ultraviolet radiation. This radiation is converted into visible light by means of fluorescent substances applied to the inside of the lamp.
Types of HQI spots
Depending on the pressure of the filling gas in the gas discharge lamp, we speak of low-pressure or high-pressure gas discharge lamps. HQI spots belong to the latter category. The pressure in these lights can go from a few dozen bar to more than 100 bar.
Our range of HQI spots consists of HQI spots of 70 Watts, 150 Watts, 250 Watts and 400 Watts. Loose HQI lamps of 70 Watts or 150 Watts are available in the colours blue, green, red, magenta and bright white.